Poor coordination of hand grip force with external loads during activities of daily living is characteristic of hand function impairment among neurological patients and the elderly. However, there is an apparent lack of objective, quantitative tests of hand function for such individuals. The main aim of the proposed pilot study is to reveal specific aspects of hand function impairment in multiple sclerosis patients (MS) using a recently developed device that allows for testing of coordination of the hand grip with external load. MS patients and healthy controls will be tested on exerting different temporal profiles of the compression/tension force (CT) applied on a rod-like device while holding it either with one or with both hands. The indices of the accuracy of exerting CT, the level of hand grip force relative to CT and coordination of hand grip and CT observed in MS will be compared with the same variables in healthy subjects. The obtained indices of hand grip coordination will also be compared with standard clinical assessment values. The proposed research is expected to reveal the particular testing conditions and experimental variables that provide strong relationships between the derived indices of hand grip impairment and clinical assessments of the tested patients, as well as the prominent differences between the patients and healthy individuals. Funding of this RO3 proposal will allow the PI to submit a subsequent R01 focused on the following areas: (1) to more comprehensibly explore those testing conditions and variables that suggest particular clinical relevance, (2) design longitudinal studies aimed to assess the success of rehabilitation procedures, (3) extend this approach to other neurological diseases, and (4) eventually propose a simple and inexpensive version of the current experimental device, as well as a simplified experimental protocol that could serve as a clinical test of hand function for MS and, possibly, other neurological patients.